The association between drinking water salinity and hypertension in coastal Bangladesh

Aims: This study aims to explore the association between drinking water salinity and hypertension in three coastal sub-districts of Bangladesh. Methods: The study uses complete data on 6,296 individuals extracted from the latest Bangladesh Poverty and Groundwater Salinity Survey and a mixed-effects logistic regression model as the analytical tool. Results: Mixed-effects logistic regression analysis shows a significant association of medium or higher-level salinity with hypertension (adjusted odds ratio 1.650, 95% confidence interval: 1.101‒2.473). Other variables significantly associated with hypertension are age, sex, education status, water source, and geographical location. A sizable proportion of the total individual-level variance in the probability of being hypertensive was at household-level (20%) and cluster-level (8%). Conclusion: The findings from this study suggest that greater salinity in potable water common in coastal areas in Bangladesh is associated with increased risk of hypertension. The study refrains from asserting causality but seeks to stimulate public health and policy interventions to address the increased risk.